1. Technical Field
The present disclosure relates to the dynamic road mapping of vascular system, and more particularly to methods for guiding a catheter through a dynamically mapped vessel.
2. Discussion of Related Art
Minimally invasive catheter-guided interventions play an important role in hospitals all over the world. A catheter is a medical device which may be introduced into a body channel or blood vessel for a variety of purposes. For example, one type is known as an intra-aortic balloon catheter which is used for cardiac assistance. Such catheters are frequently introduced into the body through the femoral artery because of the large diameter and accessibility of that artery. After insertion into the femoral artery, the distal end of the catheter can be pushed through the appropriate blood vessels to the location to be treated, e.g. an occluded blood vessel near the heart. The catheter may have a proximal end extending outside the body by which a distal end is manipulated and maneuvered. Since the path along which the catheter passes is frequently tortuous, the task of guiding and positioning the catheter is often difficult. It is sometimes necessary to remove the first catheter and insert a second catheter in its place. Further, once the distal end of the catheter reaches its desired location, it is often improperly positioned or extends angularly in the wrong direction, thus precluding the effective use of the catheter.
A 3D computed tomography angiography (CTA) scan of the patient may be taken in advance of the intervention to better plan the intervention, evaluate the risk of the planned intervention, or adjust the current diagnosis. During the intervention, surgeons may rely on two-dimensional (2D) fluoroscopic images, rather than 3D images. Bone structures and vessels (if a contrast agent is added) may be visualized in the fluoroscopic images. The 2D fluoroscopic images are often of low resolution. However, the low resolution images can be enhanced by high resolution Digital Subtraction Angiography (DSAs), where only vessel structure are visible.
However, in difficult interventions, even the enhanced 2D images may not be adequate. Further, blood vessel overlap in the projection images can make it difficult to navigate the catheter to the right position. Thus, there is a need for methods of guiding a catheter that can determine and incorporate the 3D position of the catheter.